Malicious PDF — malware analysis report

Static analysis result for SHA-256 a858dcb0f2981f57…

MALICIOUS

PDF

108.8 KB Created: 2021-06-20 16:13:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 3e20b1e312239fd9b34fc56907b95d56 SHA-1: 3857f1a2070a4cb36ba39d40bdab793dfcd5575b SHA-256: a858dcb0f2981f575c60ae29e2da4a8ce2800e8e75bbaf3ee122d78d22075ab2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links, many pointing to compromised WordPress upload directories, suggesting it functions as a link farm to distribute further malicious content. The document body, though heavily obfuscated, contains references to 'Pokemon emerald tickets cheats', indicating a lure to entice users to click on the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://kozelskadm.ru/files/uploads/files/jonoxujenigidawuval.pdf In PDF document text
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607416046f49c---60168259156.pdfIn PDF document text
    • https://autoandtruckrepair.net/nbloom/fckuploads/file/31683872253.pdfIn PDF document text
    • http://www.radiopopiatej.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fec0a99cd1---nowaxuvetizukawawo.pdfIn PDF document text
    • http://inlovehuahin.com/file_media/file_image/file/duxomatutafinawesisexa.pdfIn PDF document text
    • https://majubesar.info/contents//files/govudovizinila.pdfIn PDF document text
    • http://penoplex24.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160ab50bb667d1---98370353579.pdfIn PDF document text
    • http://www.recetasyconsejos.com/wp-content/plugins/formcraft/file-upload/server/content/files/160adb5b0125e5---ziwonepumenu.pdfIn PDF document text
    • https://pediatricpotentialsnj.com/PP/PPpng/files/zazomix.pdfIn PDF document text
    • http://fairway.cc/images/blog//file/banom.pdfIn PDF document text
    • https://led7.ru/file/36193882666.pdfIn PDF document text
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c8c17fbc64a---5094470758.pdfIn PDF document text
    • https://asiaviews.org/wp-content/plugins/super-forms/uploads/php/files/sheh9m29k0mluats0vu0emvak6/65979657491.pdfIn PDF document text
    • https://upchealth.net/wp-content/plugins/super-forms/uploads/php/files/8d34190463df9ab9ae16520d9ea17ad8/sosivivak.pdfIn PDF document text
    • http://stkvn.ru/wp-content/plugins/super-forms/uploads/php/files/a4a2b9bac8121e35736d46eda70eef59/kufibenosodofibitelumudaf.pdfIn PDF document text
    • https://www.sesc.com.ua/wp-content/plugins/super-forms/uploads/php/files/q4tag05hu11hm048tr38fpqlr4/69693250567.pdfIn PDF document text
    • http://indovinandoilmondo.it/themes/userfiles//files/99549733453.pdfIn PDF document text
    • http://coreaad.com/DreamDataUpload/file/19918238573.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=pokemon+emerald+tickets+cheatsPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000160d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x160D5 5032 bytes
SHA-256: 1ca43ca801ce7287be09f4c1c2250f8659e95c4465240c3597492cb0b61976ac
font_01_sfnt_off000171af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x171AF 10928 bytes
SHA-256: 2f98054553a1a76abccaad4fa121dd95d86af6d2993fe6e6dd32185a83f9ecda
font_02_sfnt_off00019701.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x19701 4324 bytes
SHA-256: cd94ef65598b1866d0653cdd88243d989fd81359c0e770c2d3a4858f1c2f6d34